With the increasing popularity of terminal devices (for example, mobile phones, readers, tablets, etc.), users' requirements for performance of the terminal devices are increasing. Here, an important index for evaluating the performance of the terminal devices is power consumption, and a large part of the power consumption of the terminal devices results from display panels.
In order to reduce power consumption of a display panel, ambient light may be detected. Brightness of the display panel is automatically increased when it is detected that the ambient light has high intensity, and the brightness of the display panel is automatically decreased when it is detected that the ambient light has low intensity. In this way, not only the users' use requirements can be met and the users' comfort can be enhanced, but also energy-saving purposes can be achieved. How to effectively detect the brightness of the ambient light is critical to the brightness adjustment of the display panel.